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I composed this essay over much of 2026, as I was researching Beyond Vogtle — my new study (co-authored with James Boucher) of U.S. nuclear costs from the 1980s post-Three Mile Island reactors to the Vogtle 3 and 4 units completed earlier in this decade. It traces my journey from nuclear power doubter to proponent.

The story is both general and personal: what was changing in the wide world of nuclear power, energy policy and climate; and how I regarded those changes. I hope this mode of story-telling resonates with you and also provides a backdrop to “Beyond Vogtle.”

I’ve divided it into three parts on account of its length.

This installment begins at the big Washington rally called to mark the Three Mile Island reactor accident, and covers the subsequent withering of nuclear dread, the advent of virtually always-on reactor operation, and nuclear power’s stature as the least carbon-emitting energy supply technology. 

Installment #2 begins with the failure (to date) of carbon tax advocacy — “A Climate Cure No One Wanted” — and continues with the closure of Indian Point and the concurrent slow dissolve of my dream that renewable energy could do it all.

The third and final installment begins with a slight detour in which I contrast the appalling human damage from automobility with nuclear power’s increasingly remote dangers, and then return to energy policy with a fresh way to regard nuclear power’s potential contribution to decarbonizing U.S. grids.

Thank for reading. Also, be sure to download and read my new, richly detailed report, Beyond Vogtle: What History Tells Us About the Cost of New Nuclear, co-authored with James Boucher. It’s a fresh, empirically based way of looking at the cost to build nuclear plants in the U.S. Journalist Alexander Kaufman’s reviewed it earlier today for Heatmap in a scintillating story, Nuclear Is Cheaper Than We Think It is.

  — C.K.

*  *  *  *  *  *  *  *  *

I’m pro-nuclear power. Big time.

I don’t just want the U.S. to keep running its 95 extant reactors. I want us to build more. Lots more. Hundreds.

I’m not alone. Public opinion is shifting toward nuclear power. But I came to that conclusion after spending years arguing the other side. From the mid-1970s to the late 1980s, I published a raft of critical analyses that got a good deal of public attention ― and even some traction within the nuclear industry itself. My core argument was that the cost of building nuclear plants was rising much faster than the costs of competing sources of energy. The main driver, I said, was a cascade of safety-requirement changes triggered by widespread fears of reactor accidents.

That work earned me a speaking spot at the massive May 6, 1979 rally in Washington demanding a halt to reactor construction in the wake of the March 28 meltdown at Three Mile Island in Pennsylvania. In the weeks before the rally, my research was cited in hundreds of news stories. At the Capitol, I stood alongside consumer advocate Ralph Nader, the leading figure in the U.S. antinuke movement; actress Jane Fonda, whose new film, “The China Syndrome,” had eerily foretold the Three Mile Island meltdown; and folk-rock icon Jackson Browne. I told the cheering throng that nuclear power was finished.

Cost overruns and canceled reactor projects were putting billions of dollars on the line, and I spent much of the next decade in courtrooms all over the country, explaining patiently to utility regulators why investors, not customers, should bear those losses. I eventually moved on to other public policy work, sparking big-city bicycling and helping bring congestion pricing to New York. But I kept watching nuclear power and the broader energy landscape. Over time, what I saw led me to turn from skeptic to supporter. Here’s why, in eight parts.

1. Fear and Dread Recede

Ask 100 random people today what “TMI” means, and at least 90 will say “Too Much Information.” Maybe one will mention the 1979 accident at Three Mile Island.

That’s a real shift.

The 1970s were commercial nuclear power’s first decade, and the Three Mile Island accident brought it to a terrifying close. Sixty hours into the slow-unfolding crisis, as fears grew that a “hydrogen bubble” in the reactor might explode and rupture the containment dome, CBS Evening News anchor Walter Cronkite captured the nation’s dread: “The world has never known a day quite like today. It faced the considerable uncertainties and dangers of the worst nuclear power plant accident of the atomic age. And the horror tonight is that it could get much worse.”[1]

The stricken reactor was eventually stabilized. But a combination of soaring costs and public apprehension brought an end to nuclear power’s rapid expansion in the United States.

Cronkite’s warning was about Three Mile Island itself, but it seemed to foreshadow more disasters to come. Yet since 1979, the U.S. nuclear industry has accumulated nearly 20 times as much reactor operating experience as it had built up in its entire history before the meltdown, without a sequel.[2] Like the dog that didn’t bark, this quiet fadeout of reactor calamities is an overlooked shift ― and it is prompting a rethink of long-held certitudes about nuclear power.

With each passing year there are fewer people who grew up with dread from Cold War-era A-bomb drills and weapons test fallout that got bundled into nuclear power. There are more young people like Zeke, a Brooklyn high-schooler who in 2019 went to Battery Park City to greet climate activist Greta Thunberg after her sail-powered trans-Atlantic voyage, but who this past May called fears about nuclear power “over-exaggerated.”[3] (Thunberg herself has said that Germany made a mistake by phasing out its nuclear plants, since it led to a sharp rise in coal-fired electricity.)

I’ve heard the same sentiment in hundreds of casual conversations over the past decade ― at climate rallies and on Trader Joe’s checkout lines, in California and in New York. These conversations suggest that the oppositional currents that once compelled federal nuclear regulators to keep piling on costly new safety requirements are losing force.

2. Permanent Peak Performance

Even before construction costs began to soar in the 1970s, nuclear power had another Achilles heel: spotty operating performance.

Throughout the 1970s and 1980s, the U.S. nuclear power sector struggled to maintain even a 60 percent “capacity factor” ― a measure of how much of a plant’s potential output it generates. That’s a dismal rate for equipment that’s expensive to build. I know this because I researched and wrote the first full-length study of shortfalls in U.S. nuclear plant performance, in 1976.[4]

That started to change in the mid-1980s. Plants finished safety upgrades required after Three Mile Island. The industry began sharing best practices ― and mistakes to avoid. Economic incentives helped too, as utility earnings became tied to how often plants actually ran.

The turnaround has been dramatic. Since 2000, U.S. nuclear plants have averaged 90 percent capacity factor ― a huge leap from the earlier 60 percent. In effect, downtime has dropped four-fold, from 40 percent of the time to just 10 percent. Repair jobs and retrofits that used to drag on are now precision-scheduled like the train heist in “Breaking Bad.”

The higher reliability brings a huge symbolic benefit. In the 1970s, U.S. reactors seemed to stumble from one fiasco to the next. In Alabama, a technician using a lit candle to locate an air leak started a fire that burned through a thousand cables and knocked two brand-new reactors offline for 19 months. At some ocean-cooled plants, saltwater corroded delicate heat-transfer tubes, forcing protracted repairs. Profits and industry morale took a beating, and nuclear power became a punchline on “The Simpsons.”

Those days are long past. Nuclear power, uniquely, has blossomed into both grid bulwark and climate hero. Thanks to those higher ― much higher! ― capacity factors, each nuclear plant now displaces 50 percent more carbon-emitting power generation than it used to.[5] In fact, at a 90 percent capacity factor, a kilowatt of nuclear power delivers double or triple the climate benefit of a kilowatt of wind power (which averages 30 to 40 percent capacity factor) and roughly five times that of solar (15 to 20 percent) ― a crucial distinction that’s often missing from gushing coverage of renewable energy.

3. Climate to the Fore

Nuclear power’s newfound operational mastery would matter much less but for the urgency of the climate crisis and the persistence of U.S. and global carbon emissions. Like wind and solar, nuclear power generates electricity without burning carbon.

It is true that fossil fuels are implicated in nuclear power’s supply chain. Uranium mining uses petroleum, and enriching nuclear fuel requires electricity. But even counting upstream carbon, nuclear power’s climate footprint is smaller than that of wind, solar or hydropower, according to an authoritative 2022 analysis by a multinational team for the UN Economic Commission for Europe. (Their finding matched that of the similarly comprehensive 2018 report by the UN-chartered Intergovernmental Panel on Climate Change.[6])

That’s another big change. In nuclear power’s early years, uranium fuel enrichment was so energy-intensive that the three U.S. “gaseous diffusion” plants were said to consume 10 percent of all electricity used by American factories. But diffusion enrichment has given way to gas centrifuges and, more recently, laser isotopic separation ― methods that use 20 times less energy to isolate fissile U-235 from U-238.

The bottom line: kilowatt-hour for kilowatt-hour, nuclear-generated electricity is at least as effective as solar and wind at cutting climate pollution. Meanwhile, Hurricane Katrina, Superstorm Sandy, “heat domes” and wildfires, and, in August, the first Himalayan glacial collapse, have made once-hypothetical climate death and disruption a daily reality. More than rising electricity demand from A.I., it’s the climate crisis that’s driving renewed interest in nuclear power.

Click here for the second installment, Why I’m Pro-Nuke Now: Centerpiece.

[1] Quoted passage is from a local (PA) news site, though the archived Channel 2 broadcast it cited is no longer on line.

[2] The sole “near-miss,” and a major one, was the 2002 discovery by operators at the Davis-Besse nuclear plant near Toledo, OH of extensive corrosion of the reactor vessel head — a vital barrier against loss of coolant and release of radiation. The U.S. General Accounting Office sternly rebuked the Nuclear Regulatory Commission for failing to identify and prevent the corrosion. See GAO, Nuclear Regulation: NRC Needs to More Aggressively and Comprehensively Resolve Issues Related to the Davis-Besse Nuclear Power Plant’s Shutdown, GAO-04-415, May 2004.

[3] In-person conversation at People’s Policy Conference at the New School for Social Research in New York, May 2, 2026.

[4] C. Komanoff, Power Plant Performance: Nuclear and Coal Capacity Factors and Economics (15 MB pdf), Council on Economic Priorities, 1976.

[5] Dividing today’s 90% uptime by the former 60% yields 1.50, indicating 50 percent more kilowatt-hours per kW.

[6] IPCC Annex III report, Technology-Specific Cost and Performance Parameters, 2018. See table on p. 1333.

This concludes my three-part post. Part I, Beginning, led with the Three Mile Island accident and quickly moved to the decline of nuclear dread, the advent of fabulously reliable reactor operation, and nuclear power’s climate-hero status. Part II, Centerpiece, covered the failure of carbon tax advocacy, the premature closure of Indian Point, and the dissolution of my dream that renewable energy could do it all. This final part takes antinuclear activism to task for turning a blind eye to the far more lethal harms from unrestrained automobility, and then turns to the need to redefine “least-cost” decision rules guiding electricity investment. — C.K.

7. A More-Brutal Bête Noire

On a different, but as I’ll show, related topic: I had known for some time that deaths from being struck by a motorist were shockingly common in the U.S., with 300 a year in New York City alone. I had made that fact a central element in defending bicycling against the moral panic over ― of all things ― New York’s industrious bicycle couriers during the pre-digital 1980s. And as a bicycle commuter I had long jousted with drivers. But the death of oncologist Dr. Jie Zhang in 1994 forced me to consider driver-caused traffic violence as an assault on both public health and the moral order.

A speeding driver hit and killed Dr. Jie as she stood outside New York Hospital Cornell Medical Center on Manhattan’s East Side, where she was a pediatric AIDS researcher. She was nine months pregnant. As she lay dying, her colleagues delivered her son, who survived. The newspaper ran a photo of the newborn in his father’s arms. My wife and our week-old son were safe at home. My good fortune was hard to bear.

What were the hazards of nuclear power, next to those of motorized traffic? There was and is no agreed-upon damage ratio between the two technologies. But in my eyes, the anti-nukers’ derogatory depictions of U.S. nuclear regulators seemed better suited to officials in charge of “auto safety.” In 2009, for example, after a spate of deaths in SUV rollovers, the National Highway Traffic Safety Administration required that roofs on new vehicles be able to support three times their already swollen weight. That rule led to wider windshield-obstructing structural posts , badly expanding SUV drivers’ blind spots. The result, according to a recent New York Times report, was a tidal wave of crashes that killed hundreds of pedestrians and cyclists and injured thousands more.

As a crusading young attorney in the 1960s, Ralph Nader rocketed to fame by documenting how regulatory capture made cars excessively dangerous. His subsequent pivot to opposing nuclear power initially made sense but, over time, inadvertently left American pedestrians, cyclists, and occupants of smaller vehicles vulnerable not just to “vehicle bloat” but driver distractions and the “windshield perspective” of police, prosecutors and juries.

All the while, anti-nuclear activists keep pounding their drum, willfully ignoring U.S. reactors’ splendid post-seventies safety record (see Sections 1 & 2). With few domestic miscues to flog, they leaned instead into the faraway disasters at Chernobyl (1986) and Fukushima (2011). Those disasters were real enough, but they differed from the U.S. situation not just in location but also in root cause. Soviet and Japanese officials had downplayed reactor risks, while the U.S. nuclear enterprise had built a culture dedicated to containing them.

Even reactor radioactivity, like reactor accidents, is becoming another non-barking dog. We are half-a-century into the age of large-scale deployment of nuclear power, and not a single large-scale study has emerged that credibly pins increased morbidity and/or mortality on nuclear power plant operation. Moreover, the old Rubik’s Cube problem of nuclear waste disposal is yielding to engineered solutions. The hangup was never technical. It was political.

8. By All Means, Decarbonize

For half-a-century, nuclear power and renewable energy have circled each other like wary prizefighters.

The two weren’t simply antithetical, they were incompatible — logistically as well as culturally. One couldn’t be for both; you had to pick a side. That was the gospel of physicist Amory Lovins, whose revolutionary 1976 article in Foreign Affairs magazine, “Energy Strategy: The Road Not Taken,” upended energy policy debates and galvanized the antinuclear power movement.[12]

In Lovins’ influential framing, nukes epitomized “hard” energy — lumbering and brittle. Renewables — wind and solar — were “soft” — home-grown and “right-sized.” (This was before the relentless push for engineering efficiencies turned wind turbines into colossi and blanketed entire fields with solar panels.)

Fifty years on, the climate crisis has entered the ring and demanded that the rivals partner up. The choice now is carbon-burning vs. carbon-free. Further, the perilous timeline of the crisis has toppled another dictum, also traceable to Lovins: that the transition from fossil fuels must proceed under a “least-cost-first” hierarchy that turns to costlier energy sources only after first exhausting all of the less-expensive ones.

Once, that logic was persuasive. In a leisurely, decades-long transition, why not have the lowest-cost energy lead the way? Wherever a home solar array or a Great Plains wind farm could turn a profit, the thousand busy ants of capitalism could be trusted to deploy them. The climate-warping curve would bend, steadily, painlessly, bringing a more flexible and benign energy system into the bargain.

That was the idea. The reality is falling far short, as revealed by the stubborn persistence of U.S. carbon emissions.[13] The manifold causes have been touched on here; they include everything from traditional NIMBYism to viral versions built on conspiracy-mongering, along with supersized pickups, “sport utes” and the absence of robust carbon emissions pricing. The shale revolution and two Trump presidencies did their part as well, keeping fossil fuels cheap (until No. 47 made war on Iran), which added to the stock of carbon in the atmosphere and America’s stock of carbon-consuming cities and towns, farms and roadways.

In World Cup parlance, we’ve entered stoppage time. A new rule applies: nuclear power ― or any other fossil-fuel antidote ― need not pencil out as cheaper than solar or wind to merit a part in decarbonizing U.S. grids. Instead, we should pursue any energy source or energy-saving measure that displaces fossil fuel use at lesser cost than the harm caused by burning those fuels in the first place.

Think of it like the hikers’ joke about the bear: I don’t need to outrun the bear, I just need to outrun you. In the same way, new nuclear plants don’t need to be cheaper per kilowatt-hour than solar or wind. Their electricity just needs to cost less than the added climate damage that would result from burning the fossil fuels that would otherwise fill the gap. And on that test, new nuclear power plants appear likely to succeed.

Let’s break that down.

What will new U.S. reactors cost to build?

This year I applied my statistical skills and power plant knowledge to the 49 most recently built U.S. reactors. Forty-seven of them limped to completion in the dozen years following Three Mile Island. At the time, their swollen costs so ravaged U.S. electric utilities that Forbes magazine termed the U.S. nuclear power program “the largest managerial disaster in business history.”

Nevertheless, my analysis of that cost data points to a path forward. I found that even if future reactor costs track past costs, a program that builds two or more reactors at each site and uses standardized designs will allow new plants to be built for an average cost of $8,200 per kilowatt of capacity, in 2025 dollars. At that price, building and running new reactors is almost certainly a lower-cost proposition than facing the ecological and human damage from burning equivalent fossil fuels.[14]

If anything, my figure is on the pessimistic side, since it bakes in the kind of shifting regulatory requirements that drove up costs so much in the post-TMI period. Even so, it comes to just half of what it cost to build the final two reactors — Georgia Power new Vogtle 3 and 4 units ― a project that nuclear power critics dredge up at every opportunity as proof that any new U.S. nuclear plant is doomed to be uneconomical.

Just as important, the odds of future extreme overruns appear low. Using a probabilistic model, I found that the likelihood that a new twin-unit plant, built to a standardized design, will end up costing as much as Vogtle is slim ― the same odds, around 1.7%, as correctly calling six coin flips in a row.[15]

Will the long time to build new reactors undo their climate benefit?

Past nuclear plants seemed to take forever to finish. The 47 reactors whose costs I analyzed averaged nearly 12 years from initiation to completion ― a 50 percent worsening from their 1970s counterparts. Much of that added time traces back to Three Mile Island, which triggered design changes, equipment upgrades, and staffing shifts across the entire U.S. nuclear sector, each adding delays. Slowing demand for power also led some utilities to stretch out construction schedules on their own.

To nuclear power’s critics, these setbacks come with the territory. But reactors aren’t the only major infrastructure projects facing long timelines. Delays in building wind farms, transmission lines, and other accoutrements of renewable energy have prompted plenty of national hand-wringing too. Even balcony solar ― the latest face of decarbonization ― will need time to scale up. Electrical codes and fire regulations must be rewritten, and then the real challenge begins: installing roughly 25 million of these devices (at 220W each) to match the climate benefit of a single 1,000-megawatt reactor.

There’s also a déjà vu tinge to the complaint that nuclear power is too slow to help with the climate crisis. That argument easily predates Vogtle 3 and 4 ― the massive Georgia project that tested residents’ patience and wallets, but is now helping decarbonize Atlanta and hundreds of other cities. The goal isn’t to repeat Vogtle’s egregiously high cost, which doesn’t yet clear the bar set by the social cost of carbon. It’s to treat the climate fight as an ongoing effort to reduce harm by whatever effective means are available.

Balcony solar and giant nukes aren’t rivals ― they’re partners. Building Vogtle didn’t stop Georgians from putting solar panels on their roofs in 2015, and if balcony solar really is the money-saving no-brainer its supporters claim, there’s no reason it shouldn’t help rate-burdened Georgia families in 2027, too. “All hands on deck” is a cliché, but it fits here. The world has no time to wait ― it needs to decarbonize by every means available. Including nuclear power.

[12] Lovins’ Foreign Affairs article is available here. I recounted its momentous impact on energy policy and public discourse for The Electricity Journal in 10 Blows That Stopped Nuclear Power (Jan/Feb 1991).

[13] U.S. CO2 emissions circa averaged only 1 to 2 percent annual reductions over the period 2010-2025, a rate many times slower than needed to meaningfully address the climate crisis.

[14] See Komanoff & Boucher, “Beyond Vogtle,” op. cit., pp. 41-44.

[15] The chance of correctly calling six coin-tosses in a row is one-half raised to the sixth power, which is 1 in 64, or 1.56%, which more or less matches the 1.7% chance that a new nuclear plant will cost as much as or more than Vogtle 3 and 4. See Komanoff & Boucher, op. cit., Fig. 9.